反应详情

To a solution of benzyl (2R,5R)-2-methyl-5-{[(4-nitrophenyl)carbonyl]oxy}piperidine-1-carboxylate (54.3 g, 136 mmol) in THF (850 mL) and MeOH (138 mL) was added 1 N NaOH (204 mL) and water (30 mL). The solution was stirred overnight, then concentrated in vacuo. The residue was diluted with minimal brine and water and extracted twice with EtOAc. The organics were washed with brine, dried over MgSO4, filtered, and concentrated to give the titled compound as a crude, orange-yellow oil which was used without further purification. 1H NMR (400 MHz, CDCl3) δ 7.28-7.36 (m, 5H), 5.14 (d, J=3.5 Hz, 2H), 4.50 (t, J=6.8 Hz), 1H), 4.09 (d, J=8.8 Hz, 1H), 3.94 (s, 1H), 3.09 (dd, J=14.3, 1.9 Hz, 1H), 2.06-2.15 (m, 1H), 1.96 (br s, 1H), 1.75-1.83 (m, 1H), 1.66-1.72 (m, 1H), 1.24-1.32 (m, 2H), 1.16 (d, J=7.0 Hz, 2H) ppm. LRMS m/z (M+H) 250.1 found, 250.1 required.

1. concentrationconcentrated in vacuo
2. additionThe residue was diluted with minimal brine and water
3. extractionextracted twice with EtOAc
4. washThe organics were washed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated